Alnæs, who competes for Rustad IL , won the gold medal with the relay at the Rollerski Junior World Championships 2011 in Kristiansund and the bronze medal in the team sprint at the Rollerski Junior World Championships 2013 in Bad Peterstal . In December 2014 she completed her first race in the Scandinavian Cup in Lillehammer and finished 53rd in the sprint. In February 2018, she won her first Continental Cup victory in the sprint of the US Super Tour in Ishpeming . In the summer of 2019, she took second place in the sprint and 15 km mass start race at the Rollerski World Cup in Beijing , making it 19th place in the overall World Cup. In January 2020 she won the sprint at the Scandinavian Cup in Nes Skianlegg and took her first World Cup points with eighth place in the sprint at her world cup debut in Dresden .